Non-cardiac chest is related to a problem with te esophagus, the tube that connects the mouth with the stomach. One of the most common cause of non-cardiac chest is Gastroesophabeal reflux disease (GERD) aka acid reflux. Other problems unclude; muscle problems, visceral or esophageal hypersensitivity, stomach problems such as ulcers, mucle or bone problems in the chest, lung conditions or dieases of the pleura and stress, anxiety or depression